Currently, you cannot run multiple Beats together, but we are planning to create a supervisor app that is able to run multiple Beats together, including the community Beats.
Starting with alpha3, we are releasing a more generic Topbeat that collects not only system statistics but also other statistics by periodically interrogating external systems. The Beat is called Metricbeat. Here is the blog post about it.
In Metricbeat you can define
fields in the configuration file that adds some specific fields to your exported event. Here you can read more details.